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Phase transformations of model compositions of cordierite ceramic based on silicon dioxide synthesized by the micellar technology are studied by means of thermogravimetry, differential scanning analysis, and diffractometry. The formation temperature bounds of the cordierite phase in the samples are determined.

The cerium recovery in the oxalate form from spent iron–potassium catalyst for dehydrogenation of isoamylenes into isoprene was studied. The optimum conditions allowing preparation of the pure product with high degree of recovery were found. It was proved by X-ray diffraction, thermal gravimetric analysis, differential scanning calorimetry, and X-ray fluorescence analysis that the product obtained by the precipitation was cerium oxalate decahydrate containing no less than 98 wt % main substance.

Results of a study of the recovery of cerium dioxide from a spent iron-potassium catalyst for dehydrogenation of isoamylenes to isoprene are presented. The optimal conditions are found in which pure cerium dioxide can be obtained with large degree of recovery.

Method is found and substantiated for recovery of molybdenum from a spent iron-potassium catalyst for dehydrogenation of isoamylenes to isoprene. The effect of various factors (nature and concentration of the extracting agent, temperature and duration of the extraction process, and ratio between the liquid and solid phases) on the selectivity of recovery and the yield of molybdenum was studied. It is shown that molybdenum can be recycled in manufacture of iron-potassium catalysts for dehydrogenation of isoamylenes to isoprene.

Morphology, particle size, and thermal behavior of silicic acid synthesized as gel by micellar technology were determined. It was found that the micellar synthesis using a smaller-molecule solvent, organic acid with shorter hydrocarbon (hydrophobic) part, as surfactant and silicate with smaller-radius cation yields silica gel with smaller particle size and, as consequence, increases silica dispersity. The differential thermal analysis of the synthesized silica gel showed that for samples with lesser particle size the phase transition temperatures are decreased by about 30–100°C.

The influence of the reaction conditions on the characteristics of the one-step process of the dehydrogenation of 2-methylbutane or 2-methybutenes to isoprene in the presence of a new bimetallic (Pt-Sn) catalyst was studied. It was shown that this catalyst supported on a material with an optimal structure holds promise for use in the industrial-scale process for the manufacturing of isoprene via one-step dehydrogenation.

Calorimetry, thermogravimetry, X-ray diffraction analysis, and low-temperature adsorption of nitrogen were used to study the structure of bimetallic Pt—Sn catalysts on zinc–alumina spinel supports. The effect of the porous structure of the catalyst samples synthesized on their catalytic activity in dehydrogenation of 2–methyl butane was analyzed.

From the results of experiments with platinum-containing catalysts operating in the steady mode, adiabatic changes in temperature in the course of 2-metylbutane dehydrogenation to monoolefins and isoprene were calculated. Dehydrogenation of 2-methylbutane and its mixtures with methylbutenes in the 500–600°C temperature range was simulated with varying the concentrations of 2-methylbutane, methylbutenes, hydrogen, and water, the conversion, and the selectivities with respect to both isoprene and methylbutenes. The most suitable reactor designs with intermediate heating of the reaction mixture were suggested.

Phase transitions in aluminum-zirconium oxide nanocrystals prepared by coprecipitation in the anode compartment of a membrane electrolyzer are investigated by X-ray diffraction, differential thermogravimetry, and differential scanning calorimetry. The influence of the coprecipitation conditions (pH and temperature) on the chemical and phase composition of the synthesized systems is studied.

The relationship between the acid–base properties of commercial and test samples of aluminum oxides and their catalytic activity in the dehydration of α-phenylethanol was studied. It was found that, in the dehydration of α-phenylethanol, the conversion of the alcohol and the yield of styrene on a catalyst depend on the concentrations of both Bronsted and Lewis acid sites. A hypothetical mechanism of the dehydration with the participation of coordinatively unsaturated aluminum atoms and bridging oxygen ions on the alumina surface was proposed.

A comparative study was performed of changes in the composition, structure, and catalytic activity of catalysts in selective hydrogenation of C5-C9 fraction of pyrolysis naphtha. The main reasons for catalyst deactivation in the course of industrial exploitation were considered.

The effect of acetic acid introduced as modifying additive into active aluminum oxide on its structural characteristics is considered. A relationship is established between the structural characteristics, content and features of aprotic acid centers, and catalytic activity of the obtained catalysts in dehydration of methylphenylcarbinol.